Patent · US Expired

Housing and drive mechanism for screw lift of hospital bed

US5343581A · kind A · utility

30Cited by
21References
25Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 21, 1992
Grant dateSep 6, 1994
Priority date
Expiry dateOct 21, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S254/02
  • WIPO fieldMedical technology
  • WIPO sectorInstruments

Abstract

A drive mechanism for a hospital bed effects relative vertical movement of a base and a patient litter. The drive mechanism includes spaced, telescoping threaded screw assemblies, which are driven by a single electric motor through a train of gears having helical teeth oriented to offset inherent frictional forces of the screw assemblies. A support for the motor and a component of the drive train are made of electrically nonconductive materials to electrically isolate the motor, and are arranged to damp vibrations produced by the motor. Two coiled electrical cords extend between the base and patient litter, and are each received in a recess in the patient litter when the patient litter is adjacent the base. A sensor arrangement provides an electrical signal indicative of the relative vertical positions of the patient litter and base, and a manual drive arrangement is provided to permit the gear train to be manually driven.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.